Light guided center lift

ABSTRACT

Apparatus for lifting rolls of material comprising a probe with expansible jaws for engaging the center of a roll of material or any other object having a hollow core in combination with a flood light for illuminating the flat top of a roll of material. A photo cell positioned in the tip of the probe senses the lack of reflected light from the roll when positioned directly over the hole and triggers a relay which sounds a horn, lights a light or otherwise makes known to the operator that the probe is in position to be lowered into the hole.

United States Patent [191 Dalglish May 1, 1973 LIGHT GUIDED CENTER LIFTH er ran s. l ls i 2 Cherokee Avenue, St. Paul, Minn. 551 17 Filed: Jan.6, 1972 Appl. N0.: 215,754

Inventor:

US. Cl ..2l4/653, 214/658, 214/D1G. 4 Int. Cl ..B66c 1/54 Field ofSearch ..2l4/653, 658, 651, 214/674, DIG. 1, DIG. 3, DIG. 4, 620, 750,

References Cited UNITED STATES PATENTS 3,134,620 5/1964 Blaisdell..2l4/658 X FOREIGN PATENTS OR APPLICATIONS 710,434 5/1965 Canada..2l4/l BC V lllllll.

Primary Examiner-Robert G. Sheridan Assistant Examiner-George F. AbrahamAttorneyRobert M. Dunning 5 7 ABSTRACT Apparatus for lifting rolls ofmaterial comprising a probe with expansible jaws for engaging the centerof a roll of material or any other object having a hollow core incombination with a flood light for illuminating the flat top of a rollof material. A photo cell positioned in the tip of the probe senses thelack of reflected light from the roll when positioned directly over thehole and triggers a relay which sounds a horn, lights a light orotherwise makes known to the operator that the probe is in position tobe lowered into the hole.

10 Claims, 3 Drawing Figures LIGHT GUIDED CENTER LIFT BACKGROUND OF THEINVENTION In the prior art the handling of rolls of material, such aspaper, plastic, foil, or coils of wire or cable, etc., has resulted in ahigh incidence of damage to the material on the roll. To avoid this therolls have been handled and moved by an expansible probe which isinserted into the hollow center of the roll, reel or the like. Such aprobe is a subject of my issued US. Pat. No. 3,423,120 entitled CENTERLIFT." This probe is provided with a set of expansible jaws so that itcan be inserted into the center of the roll of material and engage theinner walls thereof Since the rolls are too heavy to be manually movedabout, this probe works best in conjunction with an industrial truckwhich can be used to carry the probe up to the roll and insert ittherein. However, when the probe is mounted on the front of the truckthe lifting apparatus on the truck blocks the vision of the operator sothat it is difficult to properly align the probe with the hole in thecenter of the roll of material. Because of this, time can'be lostsearching for the correct engagement position and furthermore damage tothe roll is possible if the truck is repeatedly bumped into the rollwhile searching for the hole. The present invention provides apparatusto overcome this difficulty. The device may similarly be used on a craneor walking crane where stacked rolls above eye level necessitatessearching for the center hole.

SUMMARY OF THE INVENTION Briefly, my invention contemplates mounting aprobe on a boom which is vertically pivotally mounted von brackets onthe front of an industrial truck, crane or other lifting device. Alsomounted on said brackets, as those on which the boom is mounted, is anhydraulically actuated arcuate back plate which can be moved out by anhydraulic cylinder so as to engage the outside edge of a roll ofmaterial as the truck or other mobile means approaches the said roll topick it up. Said arcuate back plate acts as a centering force byengaging the roll at two spaced points so as to pivot the boom thuscentering the probe radially over the roll of material. As a result theboom on which the lifting probe is supported will always extend directlytoward the center of the roll.

The present invention also contemplates providing a floodlight which ismounted on the boom and is directed to illuminate the top of a roll ofmaterial in the area below the tip of the probe as it is progressingover the roll. The floodlight is turned on only after the probe tip isprogressing over the top of the roll. The reflected light from the topof the roll is sensed or received by a small photo cell which is mountedin the hollow tip of the lifting probe. The signal from the photo cellmaintains a relay in an off position as long as reflected light isperceived by the photo cell. However, when the probe moves over thecenter hole in the roll of material the photo cell receives no reflectedlight and this lack of light signals through a relay to actuate a horn,light a light or actuate other signaling means to tell the operator thatthe probe is properly aligned over the hole in the roll. Upon receivingthis signal, the operator may then lower the vertical mast mechanism tolower the probe into the hole and thereby to engage the roll. As can beseen this signal permits the lifting of rolls of material where theoperator cannot visually center the probe over the hole.

Occasionally it has been found when lifting large rolls of material thatcertain layers of material within a roll of material tend to be looselywound for various reasons causing a lack of frictional contact betweenlayers. For instance, in rolls of plastic the center or inner layers ofmaterial in the roll tend to trap air between the individual layers asthe roll is being wound thus negating the frictional holding of the saidinner layers of material and thus creating a possibility of thetelescoping of the roll when attempting to lift the roll with a centerprobe. The present invention anticipates this situation by providing anarcuate back plate which is concave or otherwise formed so as to matchthe curvature of the outside of the roll. When the probe has beeninserted into the center of the roll the back plate cylinder is thenactuated to clamp the roll between the center probe and the back platethus stabilizing the roll against telescoping.

The proper sequence of operation must be maintained in order that thecombination just described will function properly and permit the liftingand moving of rolls of material with a minimum of damage to the rollresulting in a loss of material.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of mylight guided center lift mounted upon an industrial lift truck and inposition to be lowered into a roll of material having a hollow centralaperture.

FIG. 2 is a side elevational view, partly in section, showing the centerlift, the supporting boom, and the clamping and centering plateconstruction.

FIG. 3 is a horizontal sectional view of the clamping plate actuatingmechanism, the position of the section being indicated by the line 3-3of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT As indicated in FIG. 1 of thedrawings, my roll lifting apparatus A is mounted upon a typicalindustrial truck B similar to that used in factories and loading yardsfor lifting and conveying materials of various sorts. Trucks of thistype are provided with masts 10 which supports lift forks or the like.In the present construction, the mast 10 supports a pair of verticallyspaced mounting members 11 and 12 movable vertically throughout thelength of the mast. If desired, the mast may be of the telescoping typeso that the mast will extend vertically or elongate vertically in orderto lift the object to be lifted to greater heights.

The mounting members 11 and 12 are provided with a pivot plate 9 whichsupports forwardly projecting parallel lugs or ears l3 and 14respectively. A vertical mounting plate 15 is provided with rearwardlyextending ears l6 and 17 which rest upon the ears of lugs 13 and 14. Apivot shaft 19 extends through the adjacent ears 13, 16 and I4, 17 topivotally support the mounting plate with respect to the verticallymovable mounting members 11 and 12.

A boom 20 is secured to the mounting plate 15 to extend forwardly fromthe upper end thereof. The boom 20 supports a downwardly projectingprobe 21. The probe 21, in general, is similar to that described in myabove mentioned US. Pat. No. 3,423,120. This probe includes a pluralityof jaws which project outwardly from the probe and engage the walls ofthe central opening or core of the roll C. The roll C may be of anysuitable material such as paper, plastic, foil or other sheet material,or can comprise spools of wire, cable or other such material. One of themain differences between the probe 21 and the probe shown in the patentlies in the fact that the tapered tip 26 of the probe is provided withan axial socket or recess 27 designed to accommodate a small photo cell29. A flood light 30 is mounted upon the boom and positioned to directlight downwardly onto a surface beneath the probe 21 when the probe israised slightly above such a surface. For example, when the probe isslightly above the surface of a roll C, the light 30 will direct itsrays in a generally oval pattern indicated by the broken line 31 in FIG.1 of the drawings.

A boom positioning and roll clamping plate 32 is supported by themounting plate 15, and is movable toward and away from the surface of aroll engaged by the probe 21. The plate 32 is curved in transversesection either to fit the contour of the roll 22 or to provide aslightly lesser center of arcuation than the exterior of the roll C. Theplate 32 and the mounting plate 15 are provided with pairs of parallelears 33 and 34. Lever arms 35 and 36 are pivotally connected at 37 and39 respectively to the ears 33 and 34. The levers 35 and 36 arecentrally pivotally connected together as indicated at 40. Rollers 41and 42 are pivotally supported at the lower ends of the levers 35 and36, and these rollers are vertically slideable in slides 43 and 44 onthe mounting plate 15 and on the plate 32 respectively.

A cylinder 45 is pivotally connected at 46 to a bracket 47 on themounting plate 15. A roller 49 is mounted on the end of a piston rod 50actuated by a piston within the cylinder 45. The roller 49 is engageablewith a cam track 51 mounted upon the arm 36. Upon expansion of thecylinder, piston means the arms 35 and 36 are pivoted to the positionindicated in FIG. 2, forcing the plate 32 toward the probe 21.Retraction of the piston rod 50 into the cylinder 45 acts to move theplate 32 in a direction away from the probe 21 and toward the mountingplate 15.

A generally triangular cam 52a having an inclined under surface 52 issupported by the mounting plate 15. As the arms 35 and 36 pivoted towardalignment in the collapsing of the plate 32 toward the mast, the

' roller 49a engages the cam surface 52, the rollers 44 and 49a engagingbetween the curved surface of the cam 51 and the cam surface 52. The camsurface 52 greatly increases the effective force ofthe piston rod 50against the scissors-like arms when the arms 35, 36 are in nearlycollapsed condition. By the time the arm 36 pivots upwardlysufficiently, the roller 49 is engaged within the curved cam surface ofthe cam 51 as indicated in FIG. 2. In other words, the cam surface 52engages the roller 44a and forces the arm 36 away from the mountingplate 15, providing a greatly increased force tending to extend thescissor arms 35, 36 where such force is of greatest importance.

The circuit to the photo electric cell 29 includes a photo cellcontroller diagramatically illustrated at 53, a relay 54, and a horn 55.The circuit arrangement is such that the relay will actuate a circuit tothe horn or other alarm only when the photo cell detects the absence oflight. In other words, as along as the photo cell is receiving lightwhich is reflected from the surface of the roll or other such memberbeing lifted, the signal device is maintained in a non conducting or ofiposition. However, when the probe passes over the hollow center of theroll or other object being lifted, no reflected light is detected and asignal is provided to the effect that the probe is directly over thecenter of the roll. It is only necessary that the probe be lowered intothe hollow roll center. The roll is engaged by the probe and may belifted and carried from one area to another.

In the preferred method of operation, the plate 32 is moved or extendedinto the position indicated in FIG. 2 of the drawings, and the truck ismoved toward the roll. When the plate 32 engages the periphery of theroll, the curved nature of the plate causes the boom to be swung into aposition extending radially inwardly from the roll edge, the center ofthe boom extending directly over the enter of the roll. The plate 32 isslowly retracted, and the truck B is moved forwardly, the reflectedlight from the light source 30 on the surface of the roll maintainingthe relay 54 from energizing the horn or other alarm 55. When the probeend moves to a position over the center aperture of the reel, the photoelectric cell fails to receive reflected light, and the relay isactuated, actuating the horn or other signal to show that the probe isin the proper location. The probe is then lowered with the boom and theprobe is engaged in the roll. If desired, the plate 32 may be movedagainst the roll to clamp the area of the roll between the plate 32 andthe probe 21. The roll may then be lifted and carried to a desiredpoint.

As is indicated in FIG. 2 of the drawings, a cylinder 60 is pivotallysecured as indicated at 61 between suitable supporting plates 62 nearthe end of the boom. A piston in the cylinder 60 (not illustrated) isconnected to a piston rod 63 provided with a clevis 64 pivotallyconnected as indicated at 65 to an ear 66 on the plate 69. The piston inthe cylinder 60 is usually free to slide, permitting the alignment ofthe boom relative to the roll. However, the piston rod may be actuatedto pivot the boom about the axis 19 when it is so desired.

It should be understood that a number of variations and modificationsmay be made to the apparatus disclosed without departing from the spiritand scope of the invention. For example, the particular scissorsarrangement utilized to move clamp 32 in and out is only one of a numberof possible approaches that could be used for actuating clamp 32. Otherstructural variations include different types of pivoting mounts for theprobe, boom, and clamp assembly. The particular circuit arrangementshown is examplary only and should not be construed as limiting theinvention. Other types of signaling arrangements could be used toindicate when the tip of the probe is directly over the hole and therelay horn arrangement shown in the present invention is only one ofmany possibilities. The position of floodlight 30 is not critical at allto the operation of the invention. It has been found that the light canequally well be mounted exterior to the housing of the probe 21.Considering all of these variations the following claims are presentedwith the intention of covering only the patentable concepts herein.

I claim:

1. Apparatus for handling rolls of material comprismg:

a center lift probe having a means for engaging the inside of the hollowcenter of the roll of material, said probe being carried on a boom meanswhich is adapted to be lifted and lowered by a movable lifting means;

radiant energy projecting means on said boom means and positioned toilluminate an area beneath said probe;

radiant energy detecting means in said probe operable to detect andsignal the absence of reflected radiant energy.

2. The apparatus of claim 1 and in which said boom means is pivotallymounted with respect to said mova ble lifting means for pivotingmovement about a generally vertical axis.

3. The apparatus of claim 1 including a clamp means extendably mountedon said boom means and operable to engage the side of said rolls ofmaterial when said probe is engaging the center cores of said rolls.

4. The apparatus of claim 3 in which said detecting means comprises alight detector in the tip of said probe connected to provide a signalwhen no reflected light is detected thereby.

5. The apparatus of claim 3 in which said clamp means comprises aconcave plate mounted to said boom plate by a pair of scissors extenderswhich are actuated hydraulically.

6. The apparatus of claim 4 in which said clamp means comprises aconcave plate mounted to said boom plate by a pair of scissors extenderswhich are actuated hydraulically.

7. The apparatus of claim 6 in which said boom means is pivotallymounted with respect to said movable lifting means for pivoting movementabout a generally vertical axis.

8. The apparatus of claim 7 in which said projecting means comprises afloodlight mounted on said boom means.

9. The apparatus of claim 8 in which said light detector controls saidsignal through an electrical relay.

1. Apparatus for handling rolls of material comprising: a center lift probe having a means for engaging the inside of the hollow center of the roll of material, said probe being carried on a boom means which is adapted to be lifted and lowered by a movable lifting means; radiant energy projecting means on said boom means and positioned to illuminate an area beneath said probe; radiant energy detecting means in said probe operable to detect and signal the absence of reflected radiant energy.
 2. The apparatus of claim 1 and in which said boom means is pivotally mounted with respect to said movable lifting means for pivoting movement about a generally vertical axis.
 3. The apparatus of claim 1 including a clamp means extendably mounted on said boom means and operable to engage the side of said rolls of material when said probe is engaging the center cores of said rolls.
 4. The apparatus of claim 3 in which said detecting means comprises a light detector in the tip of said probe connected to provide a signal when no reflected light is detected thereby.
 5. The apparatus of claim 3 in which said clamp means comprises a concave plate mounted to said boom plate by a pair of scissors extenders which are actuated hydraulically.
 6. The apparatus of claim 4 in which said clamp means comprises a concave plate mounted to said boom plate by a pair of scissors extenders which are actuated hydraulically.
 7. The apparatus of claim 6 in which said boom means is pivotally mounted with respect to said movable lifting means for pivoting movement about a generally vertical axis.
 8. The apparatus of claim 7 in which said projecting means comprises a floodlight mounted on said boom means.
 9. The apparatus of claim 8 in which said light detector controls said signal through an electrical relay.
 10. The structure of claim 2 and including means connected to said boom for swinging said boom to extend radially relative to said roll to extend over the hollow center of the roll. 